Simulating feed network in HFSS

I am setting up a model in HFSS which involves multiple antennas fed by a combination of hybrids and transmission lines. I have set up the feed network in Ansoft Designer and was able to get the return loss at the input port feeding the whole system, but how can I then simulate this circuit in HFSS in order to see how it effects the radiation pattern? Any ideas?

Thanks in advance!